Narrative:

In 11/88 I was captain when a traffic conflict involving an aircraft believed to be on a VFR flight plan required evasive action to avoid a collision. The following is a summary of the incident. Flight had departed pit en route to ewr. We were approximately 30-40 mi northwest of broadway VOR when we received a descent clearance from FL180 to 13000'. While descending through 16700' VFR traffic was called at 12 O'clock and 3 mi, swbnd at 16500'. The traffic was spotted immediately at 12 O'clock and less than 1 mi. At this point conflict was apparent. I disconnected the autoplt making an immediate left turn of 30-40 degrees and stopped the descent, avoiding a collision with said aircraft by approximately 150' altitude clearance and 1/2-3/4 mi horizontal clearance. At the time the majority of the beverage service had been completed, and the seatbelt sign was illuminated subsequently avoiding injuries to the passenger or cabin crew. I realize that traffic avoidance is the responsibility primarily of the cockpit crew, however it is my opinion that this incident could have been avoided by a more timely call of the traffic by ATC. One contributing factor to this may have been controller workload. The VFR aircraft was apparently known traffic to ATC, however was not pointed out sooner because of sector saturation at the time.

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Original NASA ASRS Text

Title: POTENTIAL CONFLICT BETWEEN DESCENDING ACR-MLG AND CRUISING UNK VFR.

Narrative: IN 11/88 I WAS CAPT WHEN A TFC CONFLICT INVOLVING AN ACFT BELIEVED TO BE ON A VFR FLT PLAN REQUIRED EVASIVE ACTION TO AVOID A COLLISION. THE FOLLOWING IS A SUMMARY OF THE INCIDENT. FLT HAD DEPARTED PIT ENRTE TO EWR. WE WERE APPROX 30-40 MI NW OF BROADWAY VOR WHEN WE RECEIVED A DSCNT CLRNC FROM FL180 TO 13000'. WHILE DSNDING THROUGH 16700' VFR TFC WAS CALLED AT 12 O'CLOCK AND 3 MI, SWBND AT 16500'. THE TFC WAS SPOTTED IMMEDIATELY AT 12 O'CLOCK AND LESS THAN 1 MI. AT THIS POINT CONFLICT WAS APPARENT. I DISCONNECTED THE AUTOPLT MAKING AN IMMEDIATE LEFT TURN OF 30-40 DEGS AND STOPPED THE DSCNT, AVOIDING A COLLISION WITH SAID ACFT BY APPROX 150' ALT CLRNC AND 1/2-3/4 MI HORIZ CLRNC. AT THE TIME THE MAJORITY OF THE BEVERAGE SVC HAD BEEN COMPLETED, AND THE SEATBELT SIGN WAS ILLUMINATED SUBSEQUENTLY AVOIDING INJURIES TO THE PAX OR CABIN CREW. I REALIZE THAT TFC AVOIDANCE IS THE RESPONSIBILITY PRIMARILY OF THE COCKPIT CREW, HOWEVER IT IS MY OPINION THAT THIS INCIDENT COULD HAVE BEEN AVOIDED BY A MORE TIMELY CALL OF THE TFC BY ATC. ONE CONTRIBUTING FACTOR TO THIS MAY HAVE BEEN CTLR WORKLOAD. THE VFR ACFT WAS APPARENTLY KNOWN TFC TO ATC, HOWEVER WAS NOT POINTED OUT SOONER BECAUSE OF SECTOR SATURATION AT THE TIME.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.